Mechanical playing attachment for musical instruments.



PATENTED MAR. 10, 1903.

I No. 722,476.

7 E. D. AOKERMAN. MEGHANIGAL PLAYING ATTACHMENT FOR MUSICAL INSTRUMENTS.

APPLIOATI OK FILED JUNE 95, 1902.

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APPLICATION FILED-JUNE 25, 1902.

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No. 722,476. v PATENTED MAR. 10, 1903.

E. D. AGKBRMAN. MECHANICAL PLAYINGATTAGHMENT FOR MUSICAL INSTRUMENTS.

APBLIOATION FILED JUNE 26, 1902,

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EDWIN D. ACKERMAN, OF NEW YORK, N. Y.

MECHANICAL PLAYING ATTACHMENT FOR MUSICAL INSTRUMENTS.

SPECIFICATION forming part of Letters Patent No. 722,476, dated March 10, 1903. Application filed June 25,1902- Serial No. 118,133. (No model.)

To a. whom, it may concern:

Be it known that I, EDWIN D. AOKERMAN, a'

ment in combined pneumatic and friction shoe and roller mechanism for mechanical playing attachments for musical instruments.

The improvements consist, first, in means,

hereinafter described and claimed, for operat: ing the pneumatic selecting device by which the appropriate friction-shoes are broughtinto action as determined by the passage of a perforated music sheet; secondly, in devices, I

hereinafter described and claimed, for varying the touch or producing relatively loud and soft effects in the treble and bass parts of the instruments.

My improvements are especially Well adapted for use in the class of automatic or mechanical players in which a revolving friction-drum is employed for actuating the selected friction-shoes which operate the keystrikers.

In the accompanying drawings, Figure 1 is a front view of a portion of the apparatus, partly in section. Fig. 2 is a vertical transverse section of the same, showing the striking mechanism in normal position of rest. Fig. 3 is a section of the selecting and a portion of the tone-regulating devices, showing the selected striker-operating device in position to deliver its stroke. Fig. 4 is a detail view of a part of the pneumatic selecting device. Fig. 5 is a perspective view of a part of the striking and tone-regulating mechanism.

1 1 represent pedals connected by rods 2 2 with arms 3 3 keyed on separate shafts 4 4*, mounted end to end in the frame, on the outer ends of which are keyed arms 5 5*, connected by belts 6 6 with clutch-pulleys 7, on which said belts are coiled and which through the medium of ratchet-teeth 8 impart continuous rotation to the shaft 9 of the frictiondrum, 10, by which the striker-shoes are operated, as hereinafter described. The arrangement is such that the separate clutch-pulley belts 6 6, actuated by thearms 5 5, operate through their clutch-pulleys 7 and ratchetteeth 8 upon a common drum-shaft 9, so as to impart continuous rotation to this by the alternate action of the clutch-pulleys imparted by the pedals. As the pedals 1 1 are alternately relieved of pressure the clutch-belt connected with each is retracted by means of a belt 11 by the action of a tension-spring 12, connected at one end to the retraction-belt l] and at the other end to a fixed point on the frame of the machine.

The arms 3 3 are connected, respectively,

.to suction-bellows 13 13, which exhaust the air from a suction-bellows 14 common to both, connected by an exhaust-pipe 15 with an exhaust-chamber 16, one wall of which is composed of a series of diaphragms 17, which separate it from separate pneumatic chambers 18, one for each key of the instrument, which chambers are connected by individual suction-pipes 19 with apertures 20 in the trackerbar 21, over which the perforated music-sheet 22 is drawn in customary manner. The admission of air through perforations in the music-sheet and corresponding tracker-bar apertures 20 to the separate pneumatic chambers 18 selects the keys to be operated and effects their operation by causing a movement of their respective diaphragms 17.

The diaphragms 17 act upon cranks 23, pivoted at 24 in thepneumatic chest and having at their outer ends tappet crank-arms 25, (see Fig. 4,) which act against the upper ends of bell-crank levers 26, which are fulcrumed at 27 in fixed brackets 28, so that the pressure of air in the separate pneumatic chambers 18 acting through the corresponding diaphragmcranks 23 and throwing their outer crankarms 25 in the opposite direction throws the upper end of the corresponding bell-crank levers 26 to the left in Fig. 2, thereby depressing the outer end of the horizontal arm 29 of the bell-crank, the extremity of which is pivoted at 30 to a bell-crank 31, forming the heel of the friction-shoe 38 and pivoted at 32 to a horizontal lever 33, which is pivoted at its front end to a vertical rod 34, the upper end of which is pivoted to the front end of a rocking striker-arm 35, fulcrumed at 36 and acting at its outer end by a downward stroke on the corresponding key K of the instrument. Mounted in the lower end of each of the shoeheels 31 is a staff 37, on the end of which the customary segmental-formed friction-shoe 38 is mounted, the construction and position of the parts being such that when the upper end of the bell-crank 26 is thrown to the left in Fig. 2 by the admission of atmospheric pressure to the corresponding air-chamber 18 the corresponding friction-shoe 38 is thrown down into contact with the friction-drum 10, the movement of which throws up the rear end 32 of the shoe-heel 31, and thereby through the medium of the rocking lever 33 and rod 34 strikes the corresponding key of the instrument. The levers 33, interposed between the rocking shoe-heels 31 and the striker-rods 34, being fulcrumed through the medium of springs 43 against a bearing-bar 42, serve as equalizing-levers to take up any sudden movement of the shoe on its first impact with the drum and to equalize the movement imparted by the shoe to the striker-rod.

Near the upper end of each bell-crank 26 is connected a tension-spring 41, which when the pressure of the corresponding crank-arm 25 is withdrawn by the shutting off of air from the corresponding pneumatic chamber 18 and the retraction of the diaphragm 17 by customary spring action retracts the upper end of the bell-crank 26, thereby throwing up the outer end of its horizontal arm 29 and lifting the friction-shoe 38 free from the drum and restoring it to the normal position. (Shown in Fig. 2.)

Each bell-crank lever 26 is formed with a rigid arm 39, projecting downward, so as to bear against the rest 40, when the upper end of the bellcrank lever is thrown out, so as to depress the shoe into active position.

The operation of this device is as follows: Atmospheric pressure being admitted to one of the separate vacuum-chambers 18, the upper end of the corresponding bell-crank lever 26 is thrown outward, as already described, depressing the horizontal arm 29 and causing the heel of the friction-shoe to turn upon the pivot 32 as a fulcrum, thereby depressing the shoe 38 into effective contact with the frietion-drum 10. (See Fig. 3.) The bell-crank lever 26 being thus brought to stationary position against the rest 40, the pivot 30, intermediate of the ends of the heel-plate 31, becomes a fixed fulcrum, on which the frictionshoe turns by the force of the friction-drum in delivering its stroke to the key-striker. Fig. 2 shows one of the friction-shoes in normal position of rest. Fig. 3 shows it depressed in contact with the drum 10 at the beginning of its stroke. After the stroke is delivered and when the pneumatic chamber 18 is relieved of atmospheric pressure by cutting off the air the retracting-spring 41 restores the bell-crank lever 26 to normal position, leaving the friction-shoe clear of the frictiondrum and throwing its staff back against a rest 37 which may be common to all the friction-shoes.

In practice the bell-crank levers 26 are made of sheet metal, so that their central portions afford the necessary strength and rigidity, while their upper and lower ends can 'be readily turned to planes at right angles thereto, as shown in Figs. 2 and 3, to afford proper. bearings for the tappet crank-arms and the rests 40 and also to admit of their accurate adjustment by bending.

In order to modulate the tone of the bass and treble parts of the instrument, either relatively or conjointly, I provide horizontal bars 42 42, mounted endto end, so as to be capable of independent vertical sliding movement and hearing by individual springs 43 on the rear ends of the respective horizontal bars 33, to which the shoe-heels 31 are pivoted. The spring-bars 42 42 are separately connected by vertical rods 44 and 44 with the rear ends of arms 45 and 45*, keyed on separate rock-shafts 46 46, there being a pair of rods 44 connecting the two ends of the bar 42 with arms 45, (one shown,) projecting rigidly from the opposite ends of. the rock-shaft 46, and a similar pair of rods 44, connecting the two ends of the bar 42 with a corresponding pair of arms 45, (one shown,) projecting from the opposite ends of the rockshaft 46. The rock-shafts 46 and 46 are separately rotatable by horizontal levers 47 47% which project forward in convenient position to be drawn up by the fingers of the operator, While the thumbs may rest on the horizontal front bar 48 of the frame of the machine. The bar 42 is thus under control of the lever 47, and the bar 42 under control of the lever 47.

From the above description it will be apparent that upward pressure applied to the forward ends of the respective levers 4'7 47, depressing the respective spring-bars 42 42, will apply pressure through the individual springs 43 to the horizontal bars 33 in the bass or treble parts of the instrument, or both, as may be desired, and will correspondingly accentuate and strengthen the stroke imparted by the corresponding strikers 35. It stronger tones are desired in the bassnotes, the left-hand lever 47 is drawn up. If stronger tones are desired in the treble, the right-hand lever 47 is drawn up, or if stronger tones are desired in both parts of the instrument both levers are drawn up together. This is conveniently effected by the fingers of one hand by reason of the adjacent position of the two levers 47 47, as shown in Fig. 1.

The mechanism for feeding the music-sheet and governing and regulating the feed thereof, so as to control and modify the tempo, are particularly described and claimed in another application of even date herewith.

Having thus described my invention, the following is what I claim as new therein and desire to secure by Letters Patent:

1. In a mechanical playing attachment for musical instruments, the combination of a continuously-rotated friction-drum, frictionshoes adapted to be moved into operative re- IIO lation to the said drum or retracted therefrom; striking mechanism through which the friction-shoes act on the keys; bell-crank levers 26 on which the heels of the frictionshoes are fulcrumed and by which the shoes are depressed into contact with the drum and retracted therefrom; pneumatic selectingdiaphragms 17; rocking crank-shafts 23 fulcrumed at 24 in the pneumatic chest, actuated by the diaphragms 17 and having projecting crank-arms 25 hearing against the upper ends of the bell-crank levers so as to advance the same and depress the selected friction-shoes into operative position; and springs retracting said bell-crank levers and frictionshoes; substantially as described.

2. In a mechanical playing attachment for musical instruments, the combination of a friction driving-drum; friction-shoes actuated thereby; lever mechanism on which the shoeheels are fnlcrumed and by which said shoes are depressed into operative contact with the drum or retracted therefrom; levers to which the extremities of the shoe-heels are pivoted intermediately of the ends of said levers; a bar forminga common fulcrum-bearing for one end of a number of said levers; and striker-rods pivoted to the opposite ends of said levers, through which the stroke is delivered to the keys; substantially as described.

3. In a mechanical playing attachment for musical instruments,a key-selecting and tonemodulating device comprising a set of strikeroperating devices; means for bringing the selected striker-operating devices into operative relation to an actuating mechanism; equalizing-levers on which the striker-operating devices are mounted intermediately of the ends of said levers delivering the stroke by one of their ends to the strikers; springs on which the opposite ends of the equalizing-levers are fulcrumed; a common bearingbar resting on the said springs; and means for depressing said bar so as to apply greater or less pressure to the springs and thereby modify the strength of stroke delivered through said equalizing-levers, as explained.

4. In a tone-modulating device for mechanical playing attachments for musical instruments, the combination of mechanical striking mechanism for the several keys; means for actuating said key-striking mechanism; a plurality of bars forming fulcrum-bearings against which the key-striking devices act and capable of being advanced or retracted to modify the strength of stroke; and means for advancing or retracting said bearing-bars independently; whereby the strength of action of the striking mechanism may be modified at willeither throughout the keyboard or relatively in difierent parts thereof.

5. In a mechanical playing attachment for musical instruments, the combination of an operating friction-drum 10; friction-shoes and key-strikers operated thereby; and selecting-arms 26 on which the key-strikers are mounted, formed of thin metal plates with ductile ends turned at right angles to the body of the plate, and adapted to be bent to effect their adjustment relatively 'to the contact device by which they are actuated, as

described.

EDWIN D. AOKERMAN. Witnesses:

OOTAVIUS KNIGHT, JENNIE GREEN. 

